Combustion chamber



June 28, 1960 J. D. TURLAY COMBUSTION CHAMBER Filed Nov. 14, 1952 BY WmATTORNEYS States Patent Oflice Motors (Importation, Detroit, Mich.,'acorporation of Delaware Filed Nov. 14, 1952,,Sel'. No. 320,518

16 Claims. (Cl. 123- -55) This invention relates to combustion chambersfor engines and has particular relation to a form of combustion chamberespecially applicable for use in 90 V-type 8-cylinder engines forautomotive and other uses.

It has been the practice heretofore to construct conibustion chambersfor engines in the space which may be founda'vailable after the inletand exhaust valves, the spark plugs, the inlet and exhaust passages andother parts of the engine have been arrangedin a satisfactory andconventional manner. After the design of the engine head has beendetermined by the arrangement of these elements an effort is made toconstruct a combustion chamber that will efficiently and properly burnthe commercial fuels available. .Such combustion chambers have subjectto the objection that they do not satisfactorily burn fuel at highcompression ratios and without excessive detonation, pre-ignition androughness and Without the formation of excessive carbons and otherdeposits.

It is now proposed to construct a combustion chamber' capable of beingemployed in Vtyp'e and other engines for automotive and other uses andwhich will result in improved operation at high compression ratios. Itis proposed to provide a combustion chamber in which ignition occursapproximately at the middle of the combustion chamber so that the flamewill reach the most remote and diametrically opposed parts of thecombustion chamber at about the same time. However, it is proposed notto make the. combustion chamber symmetrical in normally intersectingplanes. It is proposed to elongate the combustion chamber to some extentin one plane so that the volume of charge at the ends of the combustionchamber will be greater. thanthe volume of charge at the sides of thecombustion chamber. It is also proposed to form the combustion chamberin such manner that it will comprise an elongated firing chamber ofconsiderably less depth than width and length and to provide around theperipheral edges of the firing chamber a minimum mechanical clearancespace between the head and the end of .apiston. Such clearance spacewillprovide a quench area consisting of the closelyuspaced walls forming theclearance space and between whichthe last parts of the charge will burnat the ends and the sides of the combustion chamber. In order to providea relatively smooth running engine. it is proposed to position the.ignition means at theapex of obliquelydisposed side and end wallsforming the firing chamber in the head of the engine, so that the flamefront will progressively increase as it moves awayfrom' the place ofignition. It is also proposed. to construct the rnechanical spacecommunicating with the edgesJof the-firing chamber by a continuation ofsuch obliquely disposed walls on both the head and piston of a cylinder"of the engines.

This .will cause the quench. area to increase progressivelyafter tl ieflame front reaches the mechanical clearance space ,It is proposed toplace the valves in the side walls of the head and beside the ignitionmeans and in such position as partly to overlap both the firing chamherand clearance space. When both valves are positioned in one side wall ofthe cavity formed inthe head" as is done for the purpose of.illustration, then it is proposed to position the ignition meanssomewhat nearer the exhaust valve end of the chamber than the inletvalve end. It is considered desirable to in effect reduce the charge inthis end of the combustion chamber, due to the fact that the heatedexhaust valve will tend to cause the charge in the exhaust valve end ofthe chamber to burn somewhat faster and to develop higher tempe'ratur'esand pressures than the charge in the inlet valve end of the chamber. Itis further proposed to create a relatively uniform mechanical turbulencein all parts of the combustion chamber, for the purpose of scrubbing allofthe surfaces forming the combustion chamber. This scrubbing will tendto prevent the formation of and to cool outwardly projecting particlesof carbon and other. deposits which may otherwise be formed excessively'and may become overheated and cause pre-ignition in the engine. As thepiston approaches outer dead center on a'cornpression stroke of theengine the shape of the combustion chamber walls will create an inwardlydirected and cone shape blast of fluid forming in the charge. Thevarious elements of this blast will be parallel to the principal wallsof the combustion chamber that might collect such outwardly projectingparticles and are directed to converge upon the ignition means, therebyscrubbing the ignition means and preventing the forma-- tion of. suchparticles on the ignition means or in the vicinity thereof. When theelements of this cone shape blast meet at the ignition means there willoccur a violent and concentrated flow of fluid at the ignition meanswhich will reverse in direction at the ignition means. This reversal inthe flow of thecharge will cause the density and quality of the mixtureat the ignition means to be so increased that it will be possible undercertain conditions to burn leaner mixtures in the engine. Such reversalin the flow of fluid at the ignition means and. the tendency of thefluid thereafter to fioW axially of the cylinder and toward thelendofthe piston will cause violent local turbulence in the part of thecharge being compressed in. the firing chamber. This will cause a veryrapid burning ofthe greater part of the charge within the firing chamberwhich is in directly opposed relation to the ignition means. After thegreater part of the charge has quickly burned in the firing chamber theremaining parts of the charge will burn more slowly in the clearancespaceof the combustion chamber. This slower burning-in the clearancespace will result from the relatively coolwalls that form the turbulencecreating means and the quench area in the combustionchamberh I 1.iedraWiigS:f.. Figuife l'jillustrates afragmentary cross-sectional view of an8-cylinder 901 V-type internal combustionengine f 1 1g. combustion.chambers constructed according to e P iples of the invention. X Figure2. is.a view.takensubstantially in the plane of line on .Fig'urel andillustrating a fragmentary longitudinal sectional view of one bank ofcylinders of theengine. a e Y through the head of theengine andillustrating the posi-' tion of the valves ina somewhat enlarged cavityformed in a side wall forming apart of the combustion chant ber of theengine. Figure is taken substantially i laneof line 3 on Figure 1 lookig in the direct on j ofthe a rows thereon. ff T Figure 4 is afragmentary plan view of the of one ofthe heads; of the engineandillustratl a formed. Figure 4 is taken substantially in the plane ofline 4-4 on Figure 1.

The engine embracing the invention comprises an engine block 11 formedto provide rows or banks 12 and 13 of cylinders 14 and the axes of whichare obliquely disposed with respect to an intermediate plane through theaxis of rotation of the engine. The axes of the rows of cylinders 14 inthe present instance are arranged at 90 with respect to one anotheralthough they may be arranged at any other angle which may be desired.

The cylinders 14 have pistons 16 adapted to be connected by connectingrods 17 to a single crankshaft which may be provided for operating thetwo rows of cylinders. The cylinder banks 12 and 13 have heads 18 and 19in which inlet and exhaust passages 21 and 22 are respectively providedfor the purpose of supplying combustible mixture and of exhausting theproducts of combustion from the cylinders 14. The inlet and exhaustvalves 23 and 24 are provided for each of the cylinders 14 and arearranged in rows in each bank of cylinders with the axes of the valvesdisposed in planes parallel to the intermediate plane of the engine. Thevalves 23 and 24 are provided with valve actuating mechanisms in theform of springs 26, rocker arms 27, rocker shafts 28 and push rods 29,all of which are operated by a camshaft with which the engine 10 may beprovided.

The combustion chambers 31 of the engine which are formed as the pistons16 approach and recede from outer dead center positions in the cylindersof the engine comprise firing chambers 32 and mechanical clearancespaces 33. Combustion chambers 31 are formed by cavities 34 formed ininner walls 36 of the heads 18 and 19 and by outwardly projecting endwalls 37 of the piston 16. The cavities 34 in the heads 18 and 19 may beformed by relatively elongated and obliquely disposed side walls 33 and39 which diverge outwardly from the ends of the cylinders 14 and towardthe planes of the axm of the cylinders 14. In the present instance thewalls 39 in each bank of the cylinders 14 are arranged in the same planeand in a plane normally intersecting the intermediate plane of theengine. The walls 38 also may be normally disposed to the Walls 39 andin parallel planes on opposite sides of and parallel to the intermediateplane of the engine. The end walls of the cavities 34 are formed byobliquely disposed arcuate walls 41 that converge from within theopposite sides of the cylinders 14 toward the axes of the cylinders 14.The end walls 41 merge with the side walls 38 and 39 in relativelyarcuate corners to provide at the edges of the cavities 34 communicatingwith the ends of the cylinders '14 relatively oval shape openings withsomewhat linear sides and arcuate ends and which are disposed within andapproximates the configuration of the circular ends of the cylinders 14.

The inner surfaces of the cavities 34 may if desired be finished byboring tools operable with the axes of rotation thereof normal to theplanes of the walls 38 and 39 and movable in such planes between theendwalls 41. The ends of such tools may be normal to the axes ofrotation with the edges thereof curved inwardly so that the tool whenoperated in normally disposed planes will form a continuous curve at thejunction between the walls 38 and 39. The configuration of the surfacecut by a tool operated in this manner will provide in a plane throughthe axes of the cylinders 14 the arcuate surface configuration of theend walls 41 and in a plane normal to the axes of the cylinders 14 thesides 38 and arcuate ends 41 of the opening by which each of thecavities 34 communicates with one of the ends of the cylinders 14. Theinner surfaces of the walls 39 may be recessed to a slight extent by theapplication of another boring tool which may be employed with the axisof rotation thereof in a plane normal to the walls 39 and having an endsurface having a more planular configuration. :This will provide therecesses .42 at the opposite 4 ends of the walls 39, thereby providingthe maximum length of wall space for seating the valves 23 and 24 inside by side relation along the length of the cavity 34. The recesses 42provide sufiicient clearance at the opposite ends of the valves so thatthe flow of fluid thereto will not be interfered with by the end walls41 of the cavities 34. The pistons 16 also have the outwardly projectingends 37 thereof formed to provide side walls 43 and 44 and end walls 46.The side walls 43 and 44 are parallel to the side walls 38 and 39 of thecavities 34 and are adapted to be positioned when the pistons 16 are atouter dead centers in the cylinders 14 to lie closely adjacent to thewalls 38 and 39 and to provide 1 the side walls of the mechanicalclearance spaces indicated at 33. The end walls 46'of the outwardlyprojecting ends 37 of the pistons 16 are also formed in such a way as tobe substantially parallel to the inner surfaces of the end walls 41 ofthe cavities 34, when the pistons 16 are at outer dead center positionsin the cylinders 14. The end walls 46 are also positioned in spacedrelation to the end walls 41 to provide the remaining parts of themechanical clearance spaces indicated at 33. The outwardly projectingends of the side walls 43 and 44 and the end walls 46 also terminate innormally disposed top walls 47 which form the outer ends of the pistons16 and when the pistons 16 are at outer dead center positions in thecylinders 14, form the inner walls of the firing chambers 32. Theposition of the top walls 47 with respect to the outer ends of thecavities 34 is such as to form relatively shallow firing chambers 32that are considerably longer than they are deep. In the present instancethe walls 47 may extend into the cavities 34 a distance equal to abouthalf the depth of the cavities 34.

The combustible mixture compressed into the combustion chambers 31 onthe compression stroke of the engine may be ignited by any suitableignition means such as the spark plugs indicated at 48. The spark plugs48 are positioned in the heads 18 and 19 in rows, with the spark gapbetween the ignition terminals thereof substantially in the planes ofthe axes of the cylinders 14. The ignition terminals of the spark plugs48 also project a short distance within the inner surfaces of thecavities 34 and substantially at the apexes of the inwardly convergingwalls forming the sides and ends of the cavities 34. As will be notedfrom Figure 2 when it is desired to position the inlet and exhaustvalves in the same side wall of the cavity 34, then it is desirable toposition the ignition terminals of the spark plugs somewhat nearer theends of the firing chambers 32 in which the exhaust valves 24 arelocated. This is indicated in Figure 2 by the position of the ignitionterminals of the spark plugs 48 with respect to the axes of thecylinders 14.

In a combustion chamber formed in this manner it will be apparent thatthe charge will ignite at the terminals of the spark plug and will burnin a progressively advancing and approximately spherical flame frontacross the middle part of the firing chamber. This will substantiallydivide the charge in the firing chamber into two parts and each part ofwhich will then burn toward the end of the firing chamber. After burningacross the firing chamber the flame will then travel into the clearancespace at the sides of a combustion chamber until the charge within theclearance space also is divided into two parts. The flame will thenprogress towards the ends of the combustion chambers both from themiddle of the, clearance spaces and from the ends of the firing chambersand in which event the last parts of the charge to burn will be in theclearance spaces at the opposite ends of the combustion chambers. Sincethe firing chambers are small enough to burn a charge in two partsbefore detonation occurs and since the mechanical clearance spaces havelarge and oppositely disposed walls of progressively increasing area, itwill be apparent that the last parts of the charge in the clearancespaces at opposite ends of the combustion chambers will also burnwithout objectionable detonation, due to the decrease in" the rate offlame travel in the clearance spaces :and between the relatively coldwalls forming the quench areasand the clearance spaces.

I claim: 7 I l I l. A combustion chamber for engines comprisinganelongated cavity formed between. the head {and piston of a cylinder ofan engine, ignition means in the walls of the head" of said engine inwhich said combustion chamber is partly formed, said ignition meansbeing located in said combustion chamber between the ends and sides ofsaid combustion chamber and being closer to one end than the other ofsaid combustion chamber, a pair of inlet and exhaust valves operativelydisposed in said head with the axes thereof disposed in parallelrelation to one another and opening through said walls and into saidcombustion chamber, said inlet valve being positioned to open into theend of said combustion chamber from which said ignition means is morere,- mote and said exhaust valvebeing positioned. to open into the endof said combustion chamber with respectto which said ignition means ismore adjacent.

2. A combustion chamber for engines comprising an elongated cavityformed in the head of an engine and in directly opposed relation to thepiston of a cylinder of said engine, said cavity being formed in saidhead between elongated and planar and. obliquely disposed side walls andarcuate end walls, said Walls converging sub; stantially at-theaxis ofsaid cylinder and at a part of said cavity which is relatively moreremote from the end wall of said piston forming the oppositely disposedwall of said cavity, inlet and exhaust valve means opening into one ofsaid side walls of said cavity, and ignition means disposed in said headand substantially atjthe apex of said converging walls and at the axisof said cylinder. I

3,. A combustion chamber 'for engines comprising. a cavity formed 'inthe head of an engine in directly opposed relation to the piston of acylinder of the engine, said combustion chamber being formed in saidheadby obliquely disposed walls converging toward an apex remotefrom saidpiston and substantially on the axis of said cylinder, inlet and exhaustvalve means opening into said cavity at one side of said apex andthrough one of said walls, and ignition means disposed within saidcavity and at said apex formed by said walls.

4. A combustion chamber for engines comprising an elongated cavityformed in the head of an engine in directly opposed relation to thepiston of a cylinder of said engine, said cavity being formed in saidhead by elongated and obliquely and oppositely disposed side walls andby oppositely disposed end walls, said side and end walls converging inan elongated surface extending between said side walls transverselyacross the c axis of said cylinder and remote from said piston, an

inlet valve opening into said cavity through one of said side Walls, anexhaust valve opening into said cavity through one of said side walls,and ignition means disposed in said cavity and substantially at themiddle of said elongated surface between said converging side walls.

5. A combustion chamber for engines comprising a cavity formed betweenthe head and the piston in a cylinder of an engine, the surfaces formingsaid cavity being formed in said head by a pair of obliquely disposedwalls extending from the opposite edges of said cylinder and convergingin an elongated surface extending transversely through the axis of saidcylinder and by another pair of walls disposed normally to said firstmentioned walls and extending from opposite edges of said cylinder tothe ends of said elongated surface, the surfaces forming said cavityalso being formed in part by said piston and including a pair ofobliquely disposed walls positioned in opposed and parallel relation tosaid first mentioned walls and extending from opposite edges of saidpistonv toward Saidl'elongated sur'faceaaiid by: 3'

another pair. of lwazlls; disposed in opposed and parallel;

relati n to theadjacent parts of said; anotherxpairxof t in spaced andparallel relation to one another to'provide a quench area on theopposingnsur'faces of said walls and a minimum mechanical clearancespace between said walls, said quench area and said minimum- -mechanica1clearance space being formed outwardly from and around the" peripheraledges of a firingcham+-.

ber, formed between said piston end wall and the parts.

of said converging walls in said head and beyond said piston end wall,inlet and exhaust valve means opening into said converging walls of saidhead and in opposed relation to and extending between said firingchamber and said clearance space, and, ignition means in said ffir ingchamber at approximately the middle of said clone gated surface betweensaid converging walls of said head.

6. A combustion chamber for engines comprising a cavity formed betweenthe head and piston of a cylinder of an engine, ignition means extendingwithin the firing chamber of said combustion chamber formed by saidcavity and disposed substantially on the axisof said cylinder, saidcavity being formed :between said head and said piston byspaced'and'para'llel and obliquely disposed walls of said head and saidpiston, said obliquely disposed walls of said head and said-piston beingposi ntioned'to diverge from said ignition means toward the edges ofsaid head and said piston, said obliquely-disposed walls of said pistonbeing formed to terminate at the outer ends thereof in. a transverselydisposedzlwall-t extending across. the axis of said piston and dividing.said

combustion chamberinto. a firing chamber adjacent said ignition meansand a minimum mechanical. clearance space extending around theouteredges of said firing chamber landbetween said. obliquely disposed wallsof aid? head and said piston, and inlet and exhaust valve means eachextending through one of said obliquely disposed walls of said head andin directly opposed relation to said firing chamber and said mechanicalclearance space.

7. A combustion chamber for engines comprising a cavity formed betweenthe head and piston of a cylin-j der of an engine, ignition meansdisposed in said cavity adjacent the axis of said cylinder, an outwardlyprojecting wall formed on the end of said piston and being adapted toextend into said head and to divide said head into a firing chamberadjacent said ignition means and a minimum mechanical clearance spacearound the peripheral edges of said firing chamber and between the sidesof said outwardly disposed outwardly projecting wall of said piston andthe oppositely disposed walls of said head, said walls of said head andsaid piston being formed adjacent the peripheral edges of saidmechanical clearance space adjacent said piston and said cylinder toterminate at or Within the walls of said cylinder, and inlet and exhaustvalve means each positioned to open through one of the walls of saidhead in directly opmeans and extending with one edge of each of saidcavities in the plane of the axes of said cylinders, a row I of ignitionmeans for said cylinders having spark gap means extending into saidcavities substantially within said plane of said axes of said cylinders,a row of aligned inlet and exhaust 'valves with the axes thereofdisposed in a 'plane intersecting said plane of the axes of saidcylinders,said inlet and exhaust valves being adapted to open through awall of said head extending obliquely with respect to said plane of theaxes of said-cylinders and forming a coplanar side of each of saidtriangularly rows of cylinders, said pistons and said heads being formedto provide combustion chambers for said cylinders, a row of ignitionmeans for each of said rows of cylinders, said ignition means beingdisposed within said combustion chambers with the spark gap meansthereof disposed substantially within the planes of the axes of saidrows of cylinders, said combustion chambers in said rows of cylindersbeing formed by walls in a plane adapted to extend through both of saidrows of cylinders and between said ignition means in said rows ofcylinders and the adjacent edges of said cylinders of said rows, alignedvalves opening into said walls of said heads and between said ignitionmeans and the adjacent edges of said cylinders, said pistons also beingformed to provide top walls extending substantially normal to the axesof said cylinders and adapted upon the upward movement of said pistonsin said cylinders to form firing chambersbeyond said top walls in saidcombustion chambers and mechanical clearance spaces surrounding saidfiring chambers and communicating with the peripheral edges of saidfiring chambers.

10. An internal combustion engine comprising a row of cylinders havinghead means at one end thereof and pistons in said cylinders, combustionchambers for each of said cylinders formed between said pistons and saidhead means and formed in part by cavities extending into said headmeans, said pistons when'at the end of the compression stroke of saidpistons having ends projecting into said cavities in said head means,said ends being formed on said pistons to provide elongated and alignedand oppositely and obliquely disposed side wall surfaces connected bytop wall surfaces, said top wall surfaces being disposed normally to theaxes of said cylinders and said side wall surfaces being disposed inplanes intersecting the planes of the axes of said cylinderssubstantially at the extreme outer edges of said cavities, said cavitiesbeing formed in said head by elongated and aligned and oppositely andobliquely disposed side wall surfaces connected by arcuate and alignedsurfaces disposed in spaced and opposed relation to said topsurfaces ofsaid pistons, ignition means having spark gap terminals projecting intoeach of said combustion chambers through said arcuate wall surfaces andsubstantially within the planes of the axes of said cylinders, inlet andexhaust valves extending through said side wall surfaces on one side ofsaid cylinders and between said ignition means and the ends of saidcylinders, said side wall surfaces of said cavities and said pistonends' being disposed in closely spaced relation to one another toprovide a minimum mechanical clearance space for each of said combustionchambers, said arcuate surfaces and the adjacent ends of said side wallsurfaces of said cavities and said top wall surfaces of said pistonbeing spaced to form substantially triangularly shaped elongated andaligned firing chambers for said cylinders.

References Cited in the file of this patent UNITED STATES PATENTS

